Exemplary embodiments of the present invention relate to a device for printing, severing, and applying self-adhesive flat structures.
Such devices are known from the prior art.
Thus, a device for printing, severing, and applying self-adhesive flat structures, in particular labels, is described in DE 20 2013 103 136 U1. In this device, a carrier strip, on which an endless material strip is fastened using a pressure-sensitive adhesive, is drawn off from a supply roll and guided around a dispensing edge, at which a flat structure severed by the blade of a cutting mechanism from the material strip—for example, a label—is detached from the carrier strip and transferred to a stamp.
Labels cut to size individually to the respective task can be created by the endless material strip, so that in the event of changing label lengths, a change of the supply roll does not have to be performed, and/or supply rolls having labels of different sizes do not have to be acquired and kept ready.
To apply the flat structure severed from the material strip and held on the stamp by partial vacuum to an object to be identified, the stamp is automatically moved to this object by a handling device, the partial vacuum is canceled, and an overpressure is generated. The detachment of the label from the stamp is thus facilitated, so that the flat structure adheres with its adhesive layer on the object.
The device can have a printing device immediately before or after the cutting mechanism in the transportation direction of the carrier strip, in order to provide the flat structure with items of information.
This device has proven itself outstandingly in practice but has the disadvantage of only being able to process labels that adhere with the self-adhesive layer thereof on the carrier strip, from which the self-adhesive labels are drawn off before the application.
The carrier strip has no further use after the drawing off and application of labels, and generally has to be disposed of thermally as hazardous waste because of its chemical composition. Such a label material is thus costly to acquire and due to the obligation for proper disposal of the carrier strip.
Furthermore, a device for rolling up the carrier strip has to be provided on the labeling machine, so that the carrier strip, which is no longer required, does not interfere with the sequence of the labeling. The construction of the labeling machine is thus also made more expensive.
For this reason, label materials have been developed that dispense with a carrier strip and instead have a layer of heat-activatable adhesive on the side with which the label is to be applied to an object to be identified.
A heat-sealable label is thus described in EP 1 879 751 B1. It is accordingly provided that the label has a printable layer, a carrier layer, and a heat-sealable adhesive layer. The heat-sealable adhesive layer is a dry dispersion according to the technical teaching of EP 1 879 751 B1, which consists of polymer particles, in which at least 10% (W/W) of the total mass of polymer particles is formed by particles having an average particle diameter of at least approximately 0.5 μm, wherein the span, defined as (D90−D10)/D50, in which D10, D50, and D90 refer to the diameter of the 10% quantile, the 50% quantile, and the 90% quantile, respectively, of polymer particles, is at least 2 and the polymer particles have a coalescence temperature at or above 50° C.
A device that processes the label material according to EP 1 879 751 B1 has been presented in an article of the Danish daily newspaper “Bornholms Tidende” in the edition of 22 Sep. 2011 on page 15. The editions of this newspaper are archived in the Danish national library.
The device presented in the article has a belt applicator, by which a label unwound from a roll, printed with items of information, and discretized by a cutting device is applied to an object to be labeled which is guided past the device by a conveyor device. The label is conveyed by a belt of the belt applicator to the point that is to be provided with the label. The label is held in this case by partial vacuum on the moving belt—implemented here by a plurality of strands.
The device has a heating device, which is implemented by a heatable belt of a belt conveyor, downstream in the conveyor direction of the conveyor device, on which the object to be labeled is moved. The heat-sealable adhesive layer of the label is activated by the heatable belt, so that the applied label adhesively bonds with the surface of the object to be labeled. Alternatively, the heating device can also be arranged in the belt applicator. However, the operating principle according to which the heating device operates is not described.
This device has the disadvantage that a label is thus only applicable to one side of an object to be labeled—for example, a cuboid cardboard box—and only at one height thereon, specifically on the side that is reachable by the belt applicator and by the heating device. Furthermore, it is disadvantageous if multiple printed labels are already located beforehand on the belt conveyor and the device is therefore not suitable for real-time applications—for example, shipping address labeling or pallet labeling.
Exemplary embodiments of the invention accordingly are directed to a device for printing, severing, and applying self-adhesive flat structures, in particular labels, which overcomes the disadvantages of the prior art.
The present invention solves this problem in that the applicator is heatable by a heating device operating according to an electrical operating principle.
The heating of the applicator can thus be controlled simply and thus advantageously and the energy supply can be regulated. Furthermore, the device is real-time capable due to the heating ability of the applicator, because, due to the heating ability of the applicator, it avoids more than one label being located between printer and applicator per application procedure.
In one advantageous embodiment variant of the present invention, the heating device is formed by one or more heating wire/heating wires or heating spiral(s), which has or have a high ohmic resistance and preferably operates or operate using electrical AC voltage. The label material can thus advantageously be selected and processed without consideration of restrictions due to the type of heating. Furthermore, the material from which the respective stamp is manufactured can be freely selected without consideration of electrical properties. In addition, the label can advantageously also be combined with an RFID tag, without the RFID tag being destroyed or becoming unusable due to the type of heating.
In a further advantageous embodiment of the invention, the heating device operates with infrared radiation, plasma radiation, laser radiation, or electron beams. A heating device with low installation effort thus advantageously results.
It is furthermore advantageous for the heating device to be connected to a temperature regulator. The heat-sealable adhesive of the adhesive layer of the label is thus always melted at an optimum temperature for this purpose. Furthermore, the temperature regulator can advantageously be used for the purpose of saving energy during planned pauses.
It is also advantageous that the first plate-shaped stamp is movably mounted on the stamp-side end of the respective kinematic axis. Due to the flexible mounting, nonparallel orientations between the surface of the object to be labeled and the face of the stamp can advantageously be compensated for.
It has a particularly advantageous effect for the device to have a contact pressure device. It is advantageously ensured by the contact pressure device that the free end of the label bears over the entire area on the face of the stamp and the contact pressure device during the application procedure of the label.
In a further preferred embodiment variant of the invention, the contact pressure device has a second plate-shaped stamp, which is mounted so it is pivotable on the first plate-shaped stamp. It is easily and advantageously ensured by this advantageous embodiment of the contact pressure device that the free end of the label bears over the entire area on the face of the plate-shaped stamp and the contact pressure device during the application procedure of the label.